Abstract:
A body sensor network(BSN) is a wearable constellation of sensor nodes that collectively monitors the wearer’s vital signals. The BSN is also a highly mobile system where the embedded devices can be added to and removed from its topology dynamically and frequently. When deploying a BSN for each victim during an emergency relief operation,previously uninitialized sensor nodes placed within the same BSN need to quickly associate with one another. The problem we seek to address here is that of node estrangement. A node should be disassociated from a BSN when certain conditions satisfy and may need to be reassociated with another BSN.
This thesis targets specific aspects of the device estrangement and present a system solution that utilizes dynamic context to address the problem. We first investigate the conditions that satisfy for a device’s estrangement from its current network or system, which leads into the process of disassociation of the former owner of node from an estranged device. If the estranged device needs to join a new BSN, it will have to formally reassociate with the latter. We propose a solution that involves an experiment
which demonstrates two BSNs effectively identifying device estrangement when a sensor node is moved from one’s body to another. Each BSN will recognize a change in the context information it has collected and automatically perform the necessary disassociation or reassociation with the estranged device. We present results based on the evaluation of the system’s efficiency and security.